Validate campaign milestone target amounts

src/campaigns/campaigns.service.spec.ts

@@ -0,0 +1,73 @@
+import { BadRequestException } from '@nestjs/common';
+import { CampaignsService } from './campaigns.service';
+
+describe('CampaignsService milestone target validation', () => {
+  const prisma = {
+    campaign: {
+      create: jest.fn(),
+    },
+  };
+
+  let service: CampaignsService;
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    service = new CampaignsService(prisma as any, {} as any);
+  });
+
+  const baseDto = {
+    title: 'Orbit funding round',
+    goalAmount: '100',
+  };
+
+  it.each([
+    ['missing', undefined],
+    ['zero', '0'],
+    ['zero decimal', '0.0000000'],
+    ['below the minimum precision', '0.00000001'],
+    ['negative', '-1'],
+    ['not numeric', 'abc'],
+  ])('rejects a %s milestone targetAmount', async (_case, targetAmount) => {
+    await expect(
+      service.createCampaign('user-1', {
+        ...baseDto,
+        milestones: [
+          {
+            title: 'Prototype',
+            targetAmount,
+          },
+        ],
+      }),
+    ).rejects.toBeInstanceOf(BadRequestException);
+
+    expect(prisma.campaign.create).not.toHaveBeenCalled();
+  });
+
+  it('passes a valid positive milestone targetAmount through to Prisma', async () => {
+    prisma.campaign.create.mockResolvedValue({ id: 'campaign-1' });
+
+    await service.createCampaign('user-1', {
+      ...baseDto,
+      milestones: [
+        {
+          title: 'Prototype',
+          targetAmount: '0.0000001',
+        },
+      ],
+    });
+
+    expect(prisma.campaign.create).toHaveBeenCalledWith(
+      expect.objectContaining({
+        data: expect.objectContaining({
+          milestones: {
+            create: [
+              expect.objectContaining({
+                targetAmount: '0.0000001',
+              }),
+            ],
+          },
+        }),
+      }),
+    );
+  });
+});

src/campaigns/campaigns.service.ts

@@ -16,6 +16,8 @@ import { UpdateCampaignDto } from './dto/update-campaign.dto';
 import type { CreateUpdateDto } from './dto/create-update.dto';
 import { ContractBalanceResponseDto } from './dto/contract-balance.dto';
 
+const MIN_MILESTONE_TARGET_AMOUNT = 0.0000001;
+
 @Injectable()
 export class CampaignsService {
   constructor(
@@ -36,7 +38,7 @@ export class CampaignsService {
     const milestoneCreates = (dto.milestones || []).map((m) => ({
       title: m.title,
       description: m.description ?? null,
-      targetAmount: (m.targetAmount ?? 0) as any,
+      targetAmount: parseMilestoneTargetAmount(m.targetAmount),
       dueDate: m.dueDate ? new Date(m.dueDate) : undefined,
     }));
 
@@ -446,6 +448,19 @@ export class CampaignsService {
   }
 }
 
+function parseMilestoneTargetAmount(targetAmount?: string) {
+  const raw = targetAmount?.trim();
+  const amount = raw ? Number(raw) : Number.NaN;
+
+  if (!raw || !Number.isFinite(amount) || amount < MIN_MILESTONE_TARGET_AMOUNT) {
+    throw new BadRequestException(
+      `milestone targetAmount is required and must be at least ${MIN_MILESTONE_TARGET_AMOUNT}`,
+    );
+  }
+
+  return raw;
+}
+
 function campaignBrowseSelect() {
   return {
     id: true,

src/campaigns/dto/create-campaign.dto.ts

@@ -4,6 +4,9 @@ import {
   MaxLength,
   IsUrl,
   IsArray,
+  IsNotEmpty,
+  IsNumberString,
+  Matches,
   ValidateNested,
 } from 'class-validator';
 import { Type } from 'class-transformer';
@@ -16,10 +19,13 @@ class MilestoneInput {
   @IsString()
   description?: string;
 
-  // Accept numeric as string to be safe for Decimal columns
-  @IsOptional()
-  @IsString()
-  targetAmount?: string;
+  // Accept numeric strings to preserve precision for Decimal columns.
+  @IsNotEmpty()
+  @IsNumberString()
+  @Matches(/^(?=.*[1-9])\d+(?:\.\d+)?$/, {
+    message: 'targetAmount must be greater than 0',
+  })
+  targetAmount: string;
 
   @IsOptional()
   @IsString()