[BUG] dcc.Location callback fires twice IDENTICALLY #1049

Closed
Closed
[BUG] dcc.Location callback fires twice IDENTICALLY#1049

Description

@schmidt-jake
schmidt-jake
opened on Dec 16, 2019

As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).

importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate

Here is the output. It doesn't always print in the same order:

HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

Running on Linux. Versions used:

dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.

Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.

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      , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
       blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

      Skip to content
      [BUG] dcc.Location callback fires twice IDENTICALLY #1049
      Closed
      Closed
      [BUG] dcc.Location callback fires twice IDENTICALLY#1049
      Description
      @schmidt-jake
      schmidt-jake
      opened on Dec 16, 2019
      As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
      importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
      Here is the output. It doesn't always print in the same order:
      HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

      Running on Linux. Versions used:
      dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

      I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
      Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
      Metadata
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      Assignees
      No one assigned
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          No milestone
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          None yet
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          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

          Skip to content
          [BUG] dcc.Location callback fires twice IDENTICALLY #1049
          Closed
          Closed
          [BUG] dcc.Location callback fires twice IDENTICALLY#1049
          Description
          @schmidt-jake
          schmidt-jake
          opened on Dec 16, 2019
          As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
          importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
          Here is the output. It doesn't always print in the same order:
          HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

          Running on Linux. Versions used:
          dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

          I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
          Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            No labels
            No labels
            Type
            No type
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              [BUG] dcc.Location callback fires twice IDENTICALLY #1049
              Closed
              Closed
              [BUG] dcc.Location callback fires twice IDENTICALLY#1049
              Description
              @schmidt-jake
              schmidt-jake
              opened on Dec 16, 2019
              As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
              importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
              Here is the output. It doesn't always print in the same order:
              HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

              Running on Linux. Versions used:
              dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

              I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
              Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                No labels
                No labels
                Type
                No type
                Projects
                No projects
                  Milestone
                  No milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions
                  
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

                  Skip to content
                  [BUG] dcc.Location callback fires twice IDENTICALLY #1049
                  Closed
                  Closed
                  [BUG] dcc.Location callback fires twice IDENTICALLY#1049
                  Description
                  @schmidt-jake
                  schmidt-jake
                  opened on Dec 16, 2019
                  As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
                  importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
                  Here is the output. It doesn't always print in the same order:
                  HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

                  Running on Linux. Versions used:
                  dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

                  I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
                  Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    No labels
                    No labels
                    Type
                    No type
                    Projects
                    No projects
                      Milestone
                      No milestone
                      Relationships
                      None yet
                      Development
                      No branches or pull requests
                      Issue actions
                      
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                      Skip to content
                      [BUG] dcc.Location callback fires twice IDENTICALLY #1049
                      Closed
                      Closed
                      [BUG] dcc.Location callback fires twice IDENTICALLY#1049
                      Description
                      @schmidt-jake
                      schmidt-jake
                      opened on Dec 16, 2019
                      As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
                      importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
                      Here is the output. It doesn't always print in the same order:
                      HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

                      Running on Linux. Versions used:
                      dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

                      I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
                      Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        No labels
                        No labels
                        Type
                        No type
                        Projects
                        No projects
                          Milestone
                          No milestone
                          Relationships
                          None yet
                          Development
                          No branches or pull requests
                          Issue actions
                          
, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

                          Skip to content
                          [BUG] dcc.Location callback fires twice IDENTICALLY #1049
                          Closed
                          Closed
                          [BUG] dcc.Location callback fires twice IDENTICALLY#1049
                          Description
                          @schmidt-jake
                          schmidt-jake
                          opened on Dec 16, 2019
                          As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
                          importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
                          Here is the output. It doesn't always print in the same order:
                          HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

                          Running on Linux. Versions used:
                          dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

                          I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
                          Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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                              [BUG] dcc.Location callback fires twice IDENTICALLY #1049
                              Closed
                              Closed
                              [BUG] dcc.Location callback fires twice IDENTICALLY#1049
                              Description
                              @schmidt-jake
                              schmidt-jake
                              opened on Dec 16, 2019
                              As far as I can tell, this flavor of the "duplicate dcc.Location callback" issue (#883) hasn't been documented yet. When I run a multipage app, reloading the page fires the callback twice with the samehref / pathname / search payload. This is distinct from the other issue of having the callback return None and then returning the proper value(s).
                              importdash_core_componentsasdccimportdash_html_componentsashtmlfromdash.dependenciesimportInput, Output, Stateimportdash_bootstrap_componentsasdbcimportdashimporturllibnavbar=dbc.NavbarSimple(
brand='Frac Planning App',
brand_href='/',
sticky='top',
)
body=dbc.Container(
dbc.Row(
dbc.Col(id='page-content')
)
)
app.layout=html.Div([
dcc.Location(id='url', refresh=False),
navbar,
body
])
@app.callback(Output('page-content', 'children'), [Input('url', 'href')], [State('url', 'pathname'), State('url', 'search')])defdisplay_page(href, pathname, search):
print('HREF:', href)
print('PATHAME:', pathname)
print('SEARCH:', search)
url=urllib.parse.urlparse(href)
# print('RAW pathname:', url)print('TRIGGER(S):', [i['prop_id'] foriindash.callback_context.triggered])
ifurl.path=='/':
returnform.layoutelifurl.path=='/result':
query=dict(urllib.parse.parse_qsl(url.query))
returnresult.plot(**query)
else:
raisedash.exceptions.PreventUpdate
                              Here is the output. It doesn't always print in the same order:
                              HREF: http://houmedge201:5004/
PATHAME: /
HREF: http://houmedge201:5004/
SEARCH: PATHAME: /
TRIGGER(S): ['url.href']
SEARCH: TRIGGER(S): ['url.href']

                              Running on Linux. Versions used:
                              dash 1.7.0
dash-core-components 1.6.0
dash-html-components 1.0.2
dash-renderer 1.2.2

                              I've tried the fix mentioned in #883 (comment) to no avail. Solving this is mission critical for my app because the duplicate callback crashes a subsequent database query.
                              Changing href via a html.Link makes the callback fire only once. However, users need to be able to share app URLs with query params, which right now is broken due to this bug.
                              Metadata
                              Metadata
                              Assignees
                              No one assigned
                                Labels
                                No labels
                                No labels
                                Type
                                No type
                                Projects
                                No projects
                                  Milestone
                                  No milestone
                                  Relationships
                                  None yet
                                  Development
                                  No branches or pull requests
                                  Issue actions